There is known a gate—a device for locking a lid of a vessel operating under pressure (RU Patent 2249135; IPC F 16 J 13/16; claimed Aug. 18, 2003; published Mar. 27, 2005, Bulletin of Inventions No. 9), comprising: a lid with a mechanism for lifting thereof, said lid being installed on a body; a fast-disconnect conical-flanged joint; a lid-closing mechanism, said conical-flanged joint being made in the form of flanges of the body and the lid with a conical outer surface; and a separating device embracing ends of said flanges, said device being embodied to the shape of a pair of clips with a responsive conical drill through. Said lid-closing mechanism is provided with two hydraulic cylinders, whereas said lid-lifting mechanism is provided with a hydraulic jack, a gasket between a flange of the body and the lid is made coiled in the form of a metal framework.
The device requires a large number of mechanisms; installation of a pair of moving apart—bringing together clips may result in a uniform bringing together and tightening of the clips, particularly when the lid is sagged, and displacement of the gasket, a non-tight lid closure and unreliability of the gate operation. Moreover, the device fails to comprise safeguard elements against accidental and unauthorized depressurization.
The closets prior art with respect to the claimed technical solution is described in a fast-acting hand-driven gate (Kantorovich Z. B. “Apparatuses of Chemical Industry”, Publishing House “Mashinostroenie”, Moscow, 1965, pp. 255-257), comprising a drive in the form of a screw pair representing a trapezoidal threaded bushing with an outer surface being fitted with a nut in the form of rosette; sealing elements; a lid consisting of a flange and a bottom; a caved-in pipe (FIG. 176); stopping elements embodied to the shape of levers and fixing arms in the form of cramps with clamping bolts. Ends of said levers are freely rest on the lid. Flanges of an apparatus shell are provided with cramps adjustable for height, said cramps being attached to accommodate ends of clamping levers when the lid is closed with the initial rotation of a flywheel. In the course of subsequent rotation of a drive flywheel, rounded ends of the levers bear against the cramps while pressing the lid against the pipe through seals. The lid is finally fixed with clamping bolts.
The drawbacks to the known device consist in its unserviceability at high pressures, particularly with large diameter gates (a cantilever engagement of the lever with the cramp); inconvenience of operation (a need for adjusting height of screw cramps along the contour of a shell flange, aligning the position of rosette lugs with cramp mouths, fixing each cramp with locking screws. Moreover, the device is designed to close light, horizontally disposed lids and thus fails to comprise a turning hinge and a device for centering the lid with respect to the pipe.